// Copyright (c) 2017 Advanced Micro Devices, Inc. All rights reserved.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#include <stdio.h>
#include <gtest/gtest.h>

#include <hip/hip_runtime.h>
#include <rocrand.h>

#include <rng/generator_type.hpp>
#include <rng/generators.hpp>

#define HIP_CHECK(state) ASSERT_EQ(state, hipSuccess)
#define ROCRAND_CHECK(state) ASSERT_EQ(state, ROCRAND_STATUS_SUCCESS)

TEST(rocrand_xorwow_prng_tests, init_test)
{
    rocrand_xorwow generator; // offset = 0
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset(1);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset(1337);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset(1048576);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset(1 << 24);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset(1 << 28);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());

    generator.set_offset((1ULL << 36) + 1234567ULL);
    ROCRAND_CHECK(generator.init());
    HIP_CHECK(hipDeviceSynchronize());
}

TEST(rocrand_xorwow_prng_tests, uniform_uint_test)
{
    const size_t size = 1313;
    unsigned int * data;
    HIP_CHECK(hipMalloc(&data, sizeof(unsigned int) * size));

    rocrand_xorwow g;
    ROCRAND_CHECK(g.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int host_data[size];
    HIP_CHECK(hipMemcpy(host_data, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned long long sum = 0;
    for(size_t i = 0; i < size; i++)
    {
        sum += host_data[i];
    }
    const unsigned int mean = sum / size;
    ASSERT_NEAR(mean, UINT_MAX / 2, UINT_MAX / 20);

    HIP_CHECK(hipFree(data));
}

TEST(rocrand_xorwow_prng_tests, uniform_float_test)
{
    const size_t size = 1313;
    float * data;
    hipMalloc(&data, sizeof(float) * size);

    rocrand_xorwow g;
    ROCRAND_CHECK(g.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    float host_data[size];
    HIP_CHECK(hipMemcpy(host_data, data, sizeof(float) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    double sum = 0;
    for(size_t i = 0; i < size; i++)
    {
        ASSERT_GT(host_data[i], 0.0f);
        ASSERT_LE(host_data[i], 1.0f);
        sum += host_data[i];
    }
    const float mean = sum / size;
    ASSERT_NEAR(mean, 0.5f, 0.05f);

    HIP_CHECK(hipFree(data));
}

// Check if the numbers generated by first generate() call are different from
// the numbers generated by the 2nd call (same generator)
TEST(rocrand_xorwow_prng_tests, state_progress_test)
{
    // Device data
    const size_t size = 1025;
    unsigned int * data;
    HIP_CHECK(hipMalloc(&data, sizeof(unsigned int) * size));

    // Generator
    rocrand_xorwow g0;

    // Generate using g0 and copy to host
    ROCRAND_CHECK(g0.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int host_data1[size];
    HIP_CHECK(hipMemcpy(host_data1, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    // Generate using g0 and copy to host
    ROCRAND_CHECK(g0.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int host_data2[size];
    HIP_CHECK(hipMemcpy(host_data2, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    size_t same = 0;
    for(size_t i = 0; i < size; i++)
    {
        if(host_data1[i] == host_data2[i]) same++;
    }
    // It may happen that numbers are the same, so we
    // just make sure that most of them are different.
    EXPECT_LT(same, static_cast<size_t>(0.01f * size));

    HIP_CHECK(hipFree(data));
}

// Checks if generators with the same seed and in the same state
// generate the same numbers
TEST(rocrand_xorwow_prng_tests, same_seed_test)
{
    const unsigned long long seed = 0xdeadbeefdeadbeefULL;

    // Device side data
    const size_t size = 1024;
    unsigned int * data;
    HIP_CHECK(hipMalloc(&data, sizeof(unsigned int) * size));

    // Generators
    rocrand_xorwow g0, g1;
    // Set same seeds
    g0.set_seed(seed);
    g1.set_seed(seed);

    // Generate using g0 and copy to host
    ROCRAND_CHECK(g0.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int g0_host_data[size];
    HIP_CHECK(hipMemcpy(g0_host_data, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    // Generate using g1 and copy to host
    ROCRAND_CHECK(g1.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int g1_host_data[size];
    HIP_CHECK(hipMemcpy(g1_host_data, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    // Numbers generated using same generator with same
    // seed should be the same
    for(size_t i = 0; i < size; i++)
    {
        ASSERT_EQ(g0_host_data[i], g1_host_data[i]);
    }

    HIP_CHECK(hipFree(data));
}

// Checks if generators with the same seed and in the same state generate
// the same numbers
TEST(rocrand_xorwow_prng_tests, different_seed_test)
{
    const unsigned long long seed0 = 0xdeadbeefdeadbeefULL;
    const unsigned long long seed1 = 0xbeefdeadbeefdeadULL;

    // Device side data
    const size_t size = 1024;
    unsigned int * data;
    HIP_CHECK(hipMalloc(&data, sizeof(unsigned int) * size));

    // Generators
    rocrand_xorwow g0, g1;
    // Set different seeds
    g0.set_seed(seed0);
    g1.set_seed(seed1);
    ASSERT_NE(g0.get_seed(), g1.get_seed());

    // Generate using g0 and copy to host
    ROCRAND_CHECK(g0.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int g0_host_data[size];
    HIP_CHECK(hipMemcpy(g0_host_data, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    // Generate using g1 and copy to host
    ROCRAND_CHECK(g1.generate(data, size));
    HIP_CHECK(hipDeviceSynchronize());

    unsigned int g1_host_data[size];
    HIP_CHECK(hipMemcpy(g1_host_data, data, sizeof(unsigned int) * size, hipMemcpyDeviceToHost));
    HIP_CHECK(hipDeviceSynchronize());

    size_t same = 0;
    for(size_t i = 0; i < size; i++)
    {
        if(g1_host_data[i] == g0_host_data[i]) same++;
    }
    // It may happen that numbers are the same, so we
    // just make sure that most of them are different.
    EXPECT_LT(same, static_cast<size_t>(0.01f * size));

    HIP_CHECK(hipFree(data));
}

TEST(rocrand_xorwow_prng_tests, discard_test)
{
    const unsigned long long seed = 1234567890123ULL;
    rocrand_xorwow::engine_type engine1(seed, 0, 678ULL);
    rocrand_xorwow::engine_type engine2(seed, 0, 677ULL);

    (void)engine2.next();

    EXPECT_EQ(engine1(), engine2());

    const unsigned long long ds[] = {
        1ULL, 4ULL, 37ULL, 583ULL, 7452ULL,
        21032ULL, 35678ULL, 66778ULL, 10313475ULL, 82120230ULL
    };

    for (auto d : ds)
    {
        for (unsigned long long i = 0; i < d; i++)
        {
            (void)engine1.next();
        }
        engine2.discard(d);

        EXPECT_EQ(engine1(), engine2());
    }
}

TEST(rocrand_xorwow_prng_tests, discard_sequence_test)
{
    const unsigned long long seed = ~1234567890123ULL;
    rocrand_xorwow::engine_type engine1(seed, 0, 444ULL);
    rocrand_xorwow::engine_type engine2(seed, 123ULL, 444ULL);

    engine1.discard_subsequence(123ULL);

    EXPECT_EQ(engine1(), engine2());

    engine1.discard( 5356446450ULL);
    engine1.discard_subsequence(123ULL);
    engine1.discard(30000000006ULL);

    engine2.discard_subsequence(3ULL);
    engine2.discard(35356446456ULL);
    engine2.discard_subsequence(120ULL);

    EXPECT_EQ(engine1(), engine2());

    engine1.discard_subsequence(3456000ULL);
    engine1.discard_subsequence(1000005ULL);

    engine2.discard_subsequence(4456005ULL);

    EXPECT_EQ(engine1(), engine2());
}